The first arteries that branch off of the aorta and bring oxygenated blood to the heart muscle are the arteries.

Coronary arteries are the arteries that branch off the ascending aorta to supply the heart with oxygenated blood. The heart muscle which similar to each further organ or tissue in your body is essential of oxygen-rich blood to stay alive. Blood is delivered to the heart by its own vascular system which is called coronary circulation. The aorta the main blood supplier to the body branches off into two core coronary blood vessels also named arteries. The right coronary artery deliveries blood primarily to the right side of the heart. The right side of the heart is minor because it drives blood only to the lungs and the left coronary artery which outlets into the left anterior down artery and the circumflex artery deliveries blood to the left side of the heart. The left side of the heart is bigger and more well-developed since it drives blood to the rest of the body.

The higher you go up the less oxygen there is